1. Field of the Invention
The present invention relates to a water valve assembly, in particular a water valve assembly having a compact and space-efficient layout in which effective mixing of water, for instance hot and cold water, may be achieved.
2. Description of the Related Art
Many different water-mixing valves have been proposed previously. One of the most straightforward designs uses two valves connected respectively to hot and cold water supplies and operated manually by traditional taps or faucets, but feeding a single outlet. It is known to attach a hose and shower handset to this outlet such that a user can control a desired outlet temperature by adjusting the two respective valves. In more recent years, particularly for use with showers, it has been known to provide a single valve arrangement, which simultaneously adjusts the flow of hot and cold water into a mixing chamber. This provides very convenient operation for the user. Such arrangements may use movable ceramic plates having holes therethrough which allow simultaneous adjustment of hot and cold water-flow into the mixing chamber. Also, thermostatic arrangements are known where a user selects a desired outlet water temperature and a thermostatic element causes movement of the mixing valve to maintain that outlet temperature.
EP-A-1 128 105 and EP-A-1 229 418 describe a water-mixing valve and its associated control system. In particular, the valve includes a rotatable valve plate having tapered throughholes adjacent respective hot and cold water inlets. The plate may be rotated by a motor under the control of the control system so as to adjust simultaneously the flows of hot and cold water, thereby to provide the desired outlet mixed water temperature.